The present invention relates generally to radar systems, and more specifically, to radar sensor optimization systems.
Warning systems are being used today to alert vehicle operators of objects that may be a collision hazard. Warning systems are typically used as aids in precise parking maneuvers or while vehicles are backing up. Warning systems are desirable to minimize or avoid vehicle damage that may otherwise occur. Conventional warning systems use radar emitter/sensor systems to scan fields of coverage for objects that may be a collision hazard.
Most radar systems are threshold-type detection systems. These types of radar systems use a minimum signal target (for example, a 1-meter high, 75-mm diameter PVC pipe) as a threshold to assess the sensor""s inherent capability by placing those target objects at representative positions in the field. By placing these targets at the edge of the detection field, fewer target objects are needed. In addition, these types of radar systems are typically designed to minimize R4 range losses over all of the range bins by amplifying the signal by an incremental amount so that each effective range bin signal is essentially the same. In this way, the farthest range bin is just as sensitive as a range bin closer to the sensor.
To be used on a vehicle, a radar sensor must be adjusted based on a number of characteristics, including mounting location. The sensitivity of certain radar sensors can be adjusted by either regulating the voltage threshold of the return signal or by regulating the integration time of each dwell (or range bin). Because of the significant variation in the signal quality of radar sensors from one vehicle""s mounting configuration to another, each radar sensor must be individually adjusted. Current tuning processes are inefficient, tedious and time consuming.
It is highly desirable to create an automated method for optimizing radar sensors. The present invention creates several methods for optimizing the sensors in an efficient manner.
The present invention operates by placing target objects in a sensor""s field of coverage at strategic locations and adjusting the radar sensor""s parameters based on the target objects. Three preferred methods are used to optimize the radar sensors. The first method for optimizing sensors is accomplished by the placement of objects within the target area as a function of high bin resolution with no spatial constraints. The second method for optimizing sensors is accomplished by the placement of the objects within a target area as a function of low bin resolution with no spatial constraints. The third method of optimizing sensors is by the placement of objects within the target area with either low or high bin resolution as a function of spatial constraints.
In one embodiment, where the target area is a function of high bin resolution and no spatial constraints, a coverage area is defined for the sensor. The coverage area is divided into a series of bins, wherein each bin defines an equal portion of said coverage area at varying distances from the sensor. A target object is placed within each of the bins at a predetermined distance from the sensor. The sensor is then adjusted so that each target object is sensed by the sensor at the edge of a detection area for the sensor within each bin.
In a second embodiment, where the target area is a function of low bin resolution and no spatial constraints, a coverage area is defined for the sensor. The coverage area is divided into a series of bins, wherein each bin defines an equal portion of said coverage area at varying distances from the sensor. A target object is placed within every other of the bins at a predetermined distance from the sensor. The sensor is then adjusted so that each target object is sensed by the sensor at the edge of a detection area for the sensor within every other bin. The process is then repeated with the unused bins.
In a third embodiment, where the target area is a function of high or low bin resolution with spatial constraints, a coverage area is defined for the sensor. The coverage area is divided into a series of bins, wherein each bin defines an equal portion of said coverage area at varying distances from the sensor. A target object is placed within the furthest of the bins (away from the sensor) at a predetermined distance from the sensor. The object is then moved iteratively towards the sensor by either moving the target object or the sensor relative to each other. The sensor is then adjusted so that each target object is sensed by the sensor at the edge of a detection area for the sensor within each bin.
The methods disclosed may also be used for sensor maintenance and re-calibration, as well as for quickly and effectively administering tests for development and validation purposes.